[In the reproduction of the plates the original size has been in all cases 



slightly reduced. This must distinctly be borne in mind when 



comparing the plates with the explanations.] 



EXPI^ANATION OF PLATES. 



PLATE I. 



Phylloxera c.-septum (Shimer). 



Fig. 1. Young galls, above and beneath— natural size. 



Fig. 2. Young gall, side view -greatly enlarged. 



Fig. 3. Young galls, above and beneath— farther advanced. 



Fig. 4. Mature galls, above and beneath— natural size. 



Fig. 5. Mature galls, above and beneath —natural size. 



Fig. 6. Mature gall, vertical section— greatly enlarged. 



Phylloxera perforans Pergande, var : 



Fig. 7. Mature galls— natural size. 



Fig. 8. Mature gall, vertical section— greatly enlarged. 



